 #include <QApplication>
 #include <QFont>
 #include <QLCDNumber>
 #include <QPushButton>
 #include <QSlider>
 #include <QVBoxLayout>
 #include <QWidget>

 class MyWidget : public QWidget
 {
 public:
     MyWidget(QWidget *parent = 0);
 };

 MyWidget::MyWidget(QWidget *parent)
     : QWidget(parent)
 {
     QPushButton *quit = new QPushButton(tr("Quit"));
     quit->setFont(QFont("Times", 17, QFont::Bold));

     QLCDNumber *lcd = new QLCDNumber(2);
     lcd->setSegmentStyle(QLCDNumber::Filled);

     QSlider *slider = new QSlider(Qt::Horizontal);
     slider->setRange(0, 99);
     slider->setValue(0);

     connect(quit, SIGNAL(clicked()), qApp, SLOT(quit()));
     connect(slider, SIGNAL(valueChanged(int)),
             lcd, SLOT(display(int)));

     QVBoxLayout *layout = new QVBoxLayout;
     layout->addWidget(quit);
     layout->addWidget(lcd);
     layout->addWidget(slider);
     setLayout(layout);
 }

 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
     MyWidget widget;
     widget.show();
     return app.exec();
 }